Protect script when ram_freq is not set
Safely load PSCI DTO to enable CPUidle driver: psci_idle
The PSCI DTO shall only be applied if TF-A & Crust
support CPU idle states [0]. Otherwise the CPU usage
will be at 100%. This will not be visible in top,
lead to overheating and battery drain.
Worst case scenario would lead to a fried chip if
the CPU thermal_zone does not work or is not enabled
in DTS.
[0] https://gitlab.com/postmarketOS/pmaports/-/issues/1901#note_1238456920
The package `device-pine64-pinephone-vccq-mod` installs a u-boot user script.
The user script was loaded at address 0x50100000 partially overwriting
the initramfs (0x4FF00000-0x5015facd), and causing a boot loop.
The user script load address was increased to 0x50700000, leaving 8MB
of free space for the initramfs, the current initramfs size is 2.37MB.
